By R.J. Foster, Contributing Editor

Shortly after ancient man began banging rocks together, he discovered the seemingly magical properties released by crushing kernels of wheat (Triticum L). Hand-grinding of wheat dates back as far as 6700 B.C. in the Far East, Egypt and Rome. It was late in the 1100s that windmills in Syria, France and England began grinding wheat into flours that would become a nutritional and functional key in a world of applications.

How wheat it is

Despite rising interest in gluten-free, wheat flours still do the yeomans work. But, depending on the application, product designers need more than all-purpose white wheat flour.

Wheat flours come from six classes of wheat: Hard Red Winter, Hard Red Spring, Soft Red Winter, Hard White, Soft White and Durum. Hard wheat flours possess large jagged granules fit tightly together, making the kernel harder and more difficult to break. Soft wheat flours contain round starch granules that yield a softer, more easily broken kernel.  Hard wheat flours also differ in levels of protein, most of which is gluten.  Composed of two elementsgliadin and gluteningluten make-up and level dictate the flours functionality and suitability for a given application. 

Hard wheat flours carry high protein levels, 12% to 14%, and high-gluten strength that provides good gas-holding properties. Hard flours are well-suited for bread making. Soft wheat flours contain lower protein levels, 7% to 9%, poorer gas-retention properties, and higher amounts of starch that yield more tender textures. Used primarily in pastry, cookie and cake applications, soft wheat flours are also suitable for cereal, flat bread and cracker products. The most commonly used of all is all purpose" flour. Made from a blend of hard and soft wheat, this finely ground material brings 8% to 11% protein and good functionality in a variety of applications.

Durum is the hardest wheat with the highest protein content, typically 12% to 16%. Its yellow-colored endosperm is coarsely ground to make semolina. Looking more like sugar than flour, semolina is used to make high-quality pastas and specialty products, such as couscous. Finely ground semolina flour is referred to as durum, and is often used in noodles, such as spaghetti, vermicelli and lasagna.

Additionally, the wheat can be made from different parts of the grain. White" refined flour is made from the starchy endosperm of the kernel, and fortified to restore some B vitamins (thiamin, riboflavin and niacin) and iron. Whole grain includes the endosperm, plus the germ and bran layers, offering a higher fiber content and additional nutrients.

Special interest grains

The interest in specialized flours is increasing," notes Brook Carson, M.S., technical product manager, ADM Milling, Overland Park, KS.. Mainstream, white flour-based products continue to hold a place in the market, but many new products are adding variety with specialty flours."

One area of growing interest is the heirloom grains"forms of wheat set aside by modern growing or harvesting technologies. For example, spelt (Triticum aestivum var. spelta) is a sub-species of common wheat, that is higher in protein and B vitamins than common wheat. The grain has a tough outer husk that makes up approximately 30% to 35% of its total weight. Spelt can be used in the same types of foods as soft red winter wheat, such as pasta, high-fiber cereals and crackers. Baked goods made with spelt tend to be heavier and denser than products made from white wheat flour. Spelt is believed to be more tolerable to those with gluten sensitivity, but there are no studies to confirm this.

Said to have been taken from an Egyptian tomb, King Tuts Wheat," is today known as Kamut®, a brand name developed with the intention of preserving the identity of the ancient grain known as khorasan. Interest in khorasan is growing due to its high levels of protein, vitamins, minerals and antioxidants. A recent study conducted by the Department of Food Sciences and the Department of Biochemistry at the University of Bologna,, Italy, indicates that breads made with this unique grain can help consumers overcome the effects of oxidative stress (Frontiers in Bioscience, 2011; 16:1,609-1,618).

Interest in rye (Secale cereale) stems from its unusually high level of fiber in the endosperm, giving rye-containing products a lower glycemic index than similar products made with other grains. Ryes high fiber also increases satietya desirable benefit for dieters. Rye contains gluten, but of poorer quality than wheat, and the high level of pentosan gums tend to make sticky dough, so rye breads often are made with at least 50% wheat, but generally 60% to 75% wheat.

In 1999, FDA approved a health claim for foods made with whole grains. But, while whole grains offer health and labeling benefits, they also bring challenges for developers. Carson suggests: Whole wheat flour contains the entire kernel, bran, germ and endosperm. The bran and germ do not provide the gluten network that the endosperm does, and actually disrupts that network, making air entrapment more difficult. In more delicate formulas, like cookies and cakes, whole-grain flour may change the texture and moisture retention of the final product. The bran and germ can take on more water during mixing but lose water more quickly in the final product, possibly causing a shorter shelf life."

Goin nuts over gluten

Predicted to approach $6 billion in 2015, the market for gluten-free products has created new opportunities for flours derived from nuts.

Almond flour can be used to increase and stabilize viscosity in coverture, meringue bases and custard- style formulas," says Kelly Sayko, chef, KOR Food Innovation for Almond Board of California. The rich texture and stability of almond forms can aide in carrying flavor compounds and ensure a smooth, rich mouthfeel. The antioxidant vitamin E, naturally occurring in almonds, can assist in managing staling and moisture migration throughout the product."

According to Bruce A. Kotz, vice president, specialty products, Golden Peanut Co. LLC, Alpharetta, GA, peanut flour is an excellent option for partial replacement of traditional flours. Added to baked goods, peanut flours give them a higher protein level along with roasted peanut flavor and aroma. Peanut flour also works very well in moist baked goods, pastas and noodles, and as a dry flavoring on the surface of cereals."

Formulating with gluten-free flour sources can present formulation challenges. If peanut flour is used as the sole flour in baked goods, additional attention should be made to leavening in order to make up for the lack of structure provided by gluten," confirms Sherry Coleman Collins, MS, RD, LD, senior marketing and communications manager, National Peanut Board, Atlanta. Popular options include using chemical leavening agents or incorporating air to provide the lift and structure needed."

R.J. Foster is a Wordsmith with a B.S. in food science from the University of Wisconsin-Madison and over 15 years of experience in the food industry. He can be reached through his website, wordsmithingbyfoster.com.